汙染（pollution）是指自然環境中混入了對人類或其他生物有害的'物質，其數量或程度達到或超出環境承載力，從而改變環境正常狀態的現象。
environmental problems are becoming more and more serious all overthe world. for example, cars have made the air unhealthy for people to breatheand poisonous gas is given off by factories. trees on the hills have been cutdown and waste water is being poured continuously into hermore,wherever we go today, we can find rubbish carelessly disposed. pollution is, infact, threatening our existence.
the earth is our home and we have the duty to take care of it forourselves and for our later generations. fortunately, more and more people haverealized these problems. measures have been taken to cope with these problemsby the government. laws have been passed to stop pollution. i hope the problemwill be solved in the near future and our home will become better and better.
